Data Sheet

KA78XXE / KA78XXAE — 3-Terminal 1 A Positive Voltage Regulator
© 2006 Fairchild Semiconductor Corporation www.fairchildsemi.com
KA78XXE / KA78XXAE Rev. 1.9 21
Typical Applications (Continued)
Figure 9. Fixed Output Regulator
Figure 10. Constant Current Regulator
Notes:
33. To specify an output voltage, substitute voltage value for “XX”. A common ground is required between the input and
the output voltage. The input voltage must remain typically 2.0 V above the output voltage even during the low
point on the input ripple voltage.
34. C
I
is required if regulator is located an appreciable distance from power supply filter.
35. C
O
improves stability and transient response.
V
O
= V
XX
(1+R
2
/R
1
) + I
Q
R
2
Figure 11. Circuit for Increasing Output Voltage
0.1μF
C
O
C
I
0.33μF
Output
Input
KA78XXE
1
3
2
0.1 μF
C
O
C
I
0.33 μF
Output
Input
KA78XXE
1
3
2
Vxx
R1
R
L
I
Q
I
O
I
O
=
R
1
+
I
Q
Vxx
0.1 μF
C
O
C
I
0.33 μF
Output
Input
KA78XXE
1
3
2
Vxx
R1
R2
I
Q
I
RI
5IQ≥